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(No Medel.) 4 sheets-sheet 1. v

J. F. PLAGE. GAS ENGINE.

No. 848,999. Patented Sept. 14, 1886.

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(No Model.) 4 Sheets-Sheet 2. J. F. PLACE.

GAS ENGINE. No..348,999. Patented Sept. 14. 1886.

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4Sheets--Sheet 3. J. P. PLACE.

(No Model.)

GAS ENGINE.

Patented Sept. 14, 1886.

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J. F. PLACE.

GAS ENGINE.

' No. 848,999. Patented sept. 174, 1886..

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N. PETERS. Phanruxhagmphnr, wnshingtun. D. C.

UNITED STATES PATENT @Ferca JAMES FRANK PLACE, OF NEW YORK, N. Y.

. GAS-ENGINE.

SPECIFICATION forming part of Letters Patent N'o. 348,999l datedSeptember 14, 1886.

Application filed February 1T, 1886. Serial No. 192,184. (No model.)

To @ZZ whom it may concern:

vBe it known that I, JAMES FRANK PLACE, a citizen of the United States,residing in the city, county, and State of New York, have inventedcertain new and useful Improvements in Gas-Engines; and the following isa description and specification of the same. i

My invention relates to that class of motors or gas-engines in which theexplosive charge is compressed before ignition. It is equally applicableto the use of ordinary coal or water gas or any other inflammable gas,or to the vapor ofgasoline or other hydrocarbon liquids.

Vherever the word gas77 is used herein, it refers to inflammable gas, incontradistinction to atmospheric air.

My invention has for its object the securing of greater economy in theuse of gas, a more uniform explosive mixture, greater regularity inspeed, less annoyance from offensive odors, and greater simplicity inconstruction and ease in starting and running. To this end the4 engineisbuilt so that the burned charge is compounded77 and allowed furtherexpansion in a second cylinder, having a larger area of piston than thehigh-pressure or explosion cylinder. The amount of gas charged isvaried, according to the speed and req nirements of the engine, but ismixed with the air and is delivered to the explosion-chamber in such amanner as to retain a rich explosive mixture close to the igniter, therichness ofthe mixture being uniform, and the variation in amountof theexplosive charge being regulated by the governor, so as to increase ordiminish said amount without changing in any degree its richness orinflammability. In this case, when the speed slacks up or isdiminished, the amount of the explosive charge is increased, and theamount of the air-cushion in the explosion-chamber and cylinderiscorrespondingly diminished as each explosive charge and air charge (orcushion) is delivered to the explosion chamber, until the maximumexplosive charge is reached, or until the speed ceases to slack up andrecovers to that point for which the governor is fixed to run. If thespeed increases beyond that point, then the amount of the explosivecharge is diminished, and the amount of air charge (or cushion) in thecylinder and explosion-chamber is correl spondingly increased until thespeed ceases to increase, or fallsto that point for which the governoris set to run. Should successive and constantly more and more diminishedexplosive charges not reduce the speed to that xed point, then, when theminimum amount of the explosive charge is reached, the gas charge to thegovernor or movement of the slide-eccentric, cut off entirely, and theengine will receive no explosive charge at all until the speed lowers,when itl/will receive 'the minimum explosive chare again, the action ofthe governor being to always maintain a uniform speed.

The regulation of speed is sought to be attained in all other gasengines, so far as-I know, by one of two methods-viz., first, byreducing or increasing the richness or infiam- Inability of theexplosive charge; or, second, by skipping7 charges or delivering thesame at irregular intervals, and thus regulating the speed by the numberor frequency of the explosions. In this latter case (which is at thepresent time the most popular method) the explosions are uniform inconcussion, but very irregular in times, sometimes exploding at everyother revolution,and at times not oftener than once in tive or sixrevolutions, and unless the engine is heavily loaded the speed as anatural result is very irregular an( jerky. In the rst method abovenamed (where the engine speed is regulated by diluting the explosivecharge) the regulation is of quite limited range. For instance, when therichness or iniammability of the explosive charge is reduced or dilutedmuch below twelve of air to one of gas, the charge will not explode, andis thus wasted. The same result is reached generally when it is madericher than one of gas to six of air. Such a regulation, then, of thespeed of a gas-engine, by reducing or increasing the amount of the gasalone, (which necessarily increases ordiminishes the richness or degreeof intlammability of the explosive,) is not only very irregular,imperfect, and of limited range, but is also very wasteful of gas. Thisimportant feature of regulating the speed by varying the amount of theexplosive charge without varying its richness in gas or degree ofinflammability is attained in my present engine by the slide-valve beingdriven by an automatic cutoff governor in combination with mygas-measuringpump. This gas-measuringpumpismore fully described in myapplication for patent, Serial No. 190,692. As therein described, the lgas-supply to the pump is regulated by aslidthe gas-measuring pump is,by the action of IOO ing rod or pawl acted upon by the governorballs,which pawl or rod is acted upon in turn by a series of steps or inclineface on the igniting-slide or pump-rod, which cuts oif the gas-supply tothe gas-pump at varying points in the stroke, the stroke of thepump-piston being synchronous with thepoweipistoli. In my presentinvention the supply of gas to the gas-pump is cut off at varying pointsof the stroke by the main slide-valve, which has ports for regulatingthe supply of gas to the pump, as well as ports for connecting thehighpressure with the low-pressure cylinder. This slide-valve isoperated by an eccentric, which is varied in its position on the maincrankshaft, so as to make the stroke of the eccentric (and consequentlythat of the slide also) longer or shorter, the inlet-port opening atvery nearly the same point in the stroke at all times, while it cuts offat varying points in the stroke both the gas-inlet port to the gas-pump,and the port which connects the high-pressure and low-pressurecylinders. By this method the gas-supply to the gasmeasuring pump is cutoff earlier' or later in the stroke, and the gaseharge thus varied inamount, and by the peculiar construction of this gas-pump (more fullydescribed iu application Serial No, 190,692, referred to above,) thegas-charge is invariably mixed with that portion of the air-charge whichgoes into the explosive-chamber last, or just before the piston reachesthe limit of its outstroke (from the crank.) The areas or displacementof the lowpressure piston less the high-pressure piston, (which is theair-pump displacement,) and the gas-pump piston being in about theproportion of seven to one, the explosive charge is uniformly made inabout those proportions, regardless of an earlier or later cut-off, thussecuring invariably that explosive mixture for the charge which it mostinflammable and which gives the best results. In this way also theexplosive charge is always kept next to the igniter. The balance of theair charge, which was forced into the explosionchamber before the gascharge in the gaspump had reached that degree of compression equal tothe air charge, is unlnixed with gas, and it acts as a clearing-out orscavenger charge to clear the cylinder of carbon sparks, and it alsoacts as an air-cushion for the explosion. lt receives the heat of theexplosion, and while serving to reduce the initial pressure yet enablesme to get a larger mass under pressure for a small engine and secure thebenefit of increased expansion. This aircushion (which goes into theexplosion-chamber in advance of the explosive charge) also takes up theheat of the walls of the explosion chamber and cylinder, which augmentsits pressure, and to that extent it is in an economical point of view aclear gain. By varying the length of stroke of the slide-valve andchanging the position of the eccentric on the shaft correspondinglyunder control of the governor, the compression of the re- Massa mainderof the burned gases inthe high-pressure cylinder after the connectionbetween the ports of thetwo cylinders is closed by the slide-valve, isincreased or diminished according to earlier or later cut-off by theslide-valve. Thus in this way, in my present improvement, as the gascharge is increased (and consequently the explosive charge is larger)the compression in the high-pressure cylinder (and explosion-chamber) isdiminished, the cut-off to low-pressure cylinder being later, and as thegas charge is lessened (and explosive charge diminished in amountaccordingly) the compression is increased, the cutoff to low-pressurecylinder being earlier in the stroke. This is an important and valuablefeature in my present engine, and secures a uniform speed, and avoidsthe shocks and sudden strains which gas-engi nes hitherto have beenliable to by reason of the great variation in the different explosiveshocks. The expansion of the explosive charge after ignition in ordinarygas-engines as now built is about one volume into two or three volumes.Necessarily the terminal pressure is very high, in some cases as high asfifty pounds above the atmosphere, which involves a great loss ineconomy. y compounding orexpanding in another cylinder the terminalpressure is reduced to almost nothing, which insures a very considerablegain, the same proportion.

ally as inthe steam-engine. .ln addition the pressure on the piston isdivided between instroke and outstroke, making the engine practicallydouble-acting, and thus rendering it less difficult for the governor tomaintain a uniform speed.

The storage air-tank is not new, but with my system of valves, incombination with the slide-valve, it furnishes a very simple and veryeffective self-starter.

XVith my improvements the pressure of the compressed air from the tankacts upon both the high and low pressure pistons alternately, thusmaking it double-acting and as easily started as a steam-engine withsteam.

A large portion ofthe friction of compres sion gas-engines as now builtis due to the slide. My device (a diaphragni-spring for balancing theslidevalve,) is simple, and reduces the friction to almost nothing.

lVith my gas-measuring pump the use of the ordinary gas-reservoir orrubber bag is avoided, which is al ways more or less leaky 7 andoffensive.

In the drawings annexed hereto the same numbers in different ignresrefer' to similar parts.

Figure l is a side elevation of my engine, showing sectional view ofgas-pump. Fig. 2 is a sectional plan of the two cylinders, pistons,slide with ports, &c. Fig. 3 is aview of the crank end, showingily-wheel, automatic cut-off governor, Svc., in section. Fig. Llis aview of the cylinder end of the engine. Figs. 5, 6, and 7 are differentviews of the governor details. Fig. S is `a view of the stop-off and logTIO

IIE

-of the lever 7, raises the electric igniter and gas-inlet check, which,when the engine runs l too fast, cuts off entirely any gas-supply to thepump. Figs. 9 and 10 are sectional views of the cross-head and hollowpiston-rod. Fig. 11 is a sectional view of theslide-valve, showing themanner of balancing with the diaphragm-spring. Fig. 12 is a sectionalview of the check and screw valves to admit and retain astorage ofburned gases and air to the airtank, and for start-ing the engine withthe same when under compression.

I will now proceed to describe the operation Yof my engine, supposingthe position of the crankto be as shown in Fig. 2,the piston about tocommence on the instroke (or move toward the crank.) 1 is thehigh-pressure and 2 and 23 the low-pressure piston. 3 is theexplosion-chamber. The end 3, next to the igniter, we will. suppose tohave an explosive charge, ready for ignition, while the other part, 3,next to the cylinder, is iilled with compressed air un mixed with gas.The slide 5 moves toward the explosion-chambenand the rod 6, by meansbreaks the circuit at 4 of the electric current caused by the smalldynamo 8, Fig. 3. An intense electric spark is the result at the pointsof theigniter 4, which ignites the charge. The ire fills the chamber 3,and instantly the pressure of the charge is augmented to from six totwelve atmospheres, according to the amount of the explosive charge inthe end of the chamber at 3. This pressure iills the high-pressurecylinder 29, and acts on the piston l through the passage 26 and forcesit out into the low -pressure cylinder 9. During this movement the slide5 moves toward the explosion chamber, and in its movement the slide-port12 uncovers the port 10 and forms a connection between that and port 11,which allows the gas to enter the gas-pump 13, Fig. 1. Before the piston14 of the pump reaches, say, half-stroke the slide 5 has returned andcut off the connection between the two gasports 10 and.11, so that forthe balance of the stroke, or until the piston 14A reaches the pointshown in Fig. 1, the supply of gas being cut off, Athe piston 14 pullsagainst a partial vacuum, and on its return commences to colnpress thegas charge at the point where the supply was cut ot'f. Vhen the mainpiston 1 2 commences to move under the pressure of the explosion, avacuum is caused in the end of cylinder 9 at 15, which sucks air inthrough the cross-head 16, Fig. 9, the hollow piston-rod 17, Fig. 2, andthe perforations 18, into the recess in the large piston 2, and thencethrough the valves 19, until when the piston has reached the limit ofits instroke (toward the crank) the cylinder 9 (less the displacement ofthe high-pressure piston 1) is filled with air. At this point the slide5 moves further toward the crank-shaft, and by means oi' the port 20forms a connection between the ports 2l and 22. Theburned gases and hotair, then under high tension, rushing in through the port 22,immediately act upon the lowpressure piston on the larger area 23 whenit is in the crank end of the cylinder at 24 as the crank passes thecenter. The piston is thus forced back to the point shown in Fig. 2, andthe hot air and burned gases are thus further expanded, down to almostatmospheric pressure. W'hen the piston has reached about halfstroke inthis last movement, the air in the air-compressor end 15 of the cylinder9 will equal the pressure of the expanding burned gases, and thecompressed-air outlet-valve 25 will be forced open, and the fresh-aircharge follows the expanding burned gases through the pipe 27 into theexplosion -chamber 3. This point (when the fresh air opens the valve 25and begins to enter the explosionchamber) varies, according to theamount of and pressure generated by the previous explosion, but as theburned charge is constantly being lowered in pressure, as the piston 2moves on its outstroke, (from the erank,) the compressed air on theother side of the piston 2 at 15 is constant] y increasing i n pressure,so that when the pressures become equal one counterbalances the|other-that is, the pressure on the area ofthe low-pressure piston at 23just offsets the pressure on the high-pressure piston at 29 added to thepressure in the air-compressor at l5, and from that point it is simply adisplacement, no power being absorbed, the compressed air enteringthrough valve 25 as fast as the piston moves, and the burned gases(orold charge) receding from the explosionchamber through the passage2G, and the ports 2l. and 22 into the low-pressure cylinder, both thevolumes and pressures remaining nearly the same. Then about one-third ofthe com'- pressed air has entered the explosion-chamber 3 from thecompressor 15, the compression of the gas in the gaspump 13 (depending,of course, upon the point of cut-oft in the stroke when the gas enteredthe pump) will equal the air-pressure in the pipe 27, and will commenceto enter and mix with the column of airthrough the check-valve 28. Asthe strokes of t-he main piston andthe gas-pump piston are synchronous,and as the areas or displacement of the air-compressor and gas-pump arein proportion of about seven to one, the balance of the compressed-aircharge is thoroughly mixed with gas from the pump through the valve 28,as it (the air) passes through the pipe 27 and the valve 25 into theexplosionchamber. It will be noticed that the explosive charge fills theexplosion-chamber 3 in izo the igniter end at 3 from one-fourth to two-I thirds the capacity of the chamber, according to the amount of gas inthe gas-pump, which amount varies according to the point of cut-off ot'the slide` 5, and which point of cut-off depends entirely upon thegovernor which regulates the position of the eccentric on the shaft,(see Figs. 5, 6, and 7,) which I will now explain.

, The automatic cut-off governor (shown in Fig. 7) is not new, but itsadaptation to a gasengine is entirely new. There are several forms ofthis kind of governor used 011 the steamengine. Its operation is quitesimple: As the speed increases, the weights 30 move outward and carrythe eccentric 3.1. along ou the shaft through the slot or opening 34,the eccentric being held or pivoted at the point 35, and connected tothe governor-weights by the rods 3G. In this movement of the eccentric(to the left in Fig. 7) the centers of the eccentric and shaft 32 comenearer together, and thus shorten the stroke of the eccentric and slide5, which is driven by the rod 33, which rod is connected to the straparound the eecentric 31. n one side of the eccentric I have twolugs,wedge-shaped, 37, which fit into correspondinglywedge shapedrecesses in the sleeve or thimble 3S on the shaft. This thimble orsleeve is held in position on the shaft by the feathered key 39. Itisalso held up against the eccentric by the two springs 40, which aremade fast to thc small fixed eccentric 7l, Figs. 3 and 5, which operatesthe exhaustvalve 70, Fig. 2. On the face of this thimble or sleeve Ihave a cam or raised part, 42, which corresponds to about two-thirds ofa stroke, or, say, one hundred and twenty degrees; and l. have a pawl orlever, 43, the end of which bears against the face of the thimble 3S,and having a rod, 44, which is connected to a valve, 45, in thegas-supply pipe 10, Fig. 2, and 4G, Fig. 1, just below where it entersthe port. This pawl 43 is held in place by the stud 47, made fast to theframe. Now, when the speed increases beyond a predetermined point thegovernor-weights will carry the eccentric to the left, as shown in Fig.7, and the stroke of the slide 5 being shortened the port 12, Fig. 2,cuts off the gassupply at an earlier and earlier point in the stroke,and the gas charge admitted to the pump 13 becomes less and less. Duringthis operation the thilnble 3S is being gradually pushed by the lugs 37to the left. (See Figs. 5 and 6.) Finally, when it is not economy toreduce the gas charge further, if the speed continues to increase at apredetermined point, the cam 42 on the thimble 3S is moved away from thepawl 43, Fig. 5, and the gas-supply checkvalve 45, Fig. S, is no longerraised at all, and as a consequence no gas at all enters the gas-pump 13for the following stroke, or again until the speed lowers. The lugs 37can be placed ou the sleeve and the inclined recesses made in theeccentric, where the lugs are shown, (see Fig. 7,) or the recesses maybe dispensed with and lugs placed on both the eccentric and sleeve. Ineither case the result sought is thc samennamely, moving the sleeve andcam 42 out of contact with the lever 43 and leaving the gasvalve 45closed until the speed is reduced. As soon as the speed slacks up any,then the eccentric will move to the right, (see Fig. 7,) and the lugs 37will allow the springs 40 to push the thimble 3 to the right, as shownin Figs. 5 and 6, and the cam 42 comes in contact with the pawl 43again, which causes the gas-check valve 45 to open at regular intervalsagain. The gaseharge in the pump will. be light at first, owto theshortness of stroke and consequent early cut off; but if the speedcontinues to lower, the eccentric will continue to move to the right,(see Fig. 7,) which lengthens the stroke of the eccentric and slide 5,and the gas-supply will be cut off at a later and later point in thestroke by the port 12, Fig. 2, and the amount of gas-charge to thegas-pump will be correspondingly increased until the maximum charge isobtained. By the movement of the eccentric on the shaft under the actionof thc gov ernor, the port 20, Fig. 2, cuts off the conncc tion betweenthe two ports21 and 22 at different points in the stroke, whichvariation, however, is not as great as that of the gas cut off by port12, owing to the less amount of lap in the port 2() in uncovering theport 22. The result of this is that the high-pressure piston 1 in thelast portion of its outstroke (from the crank) compresses the air iu thecylinder 29 and explosion-chamber, and the hot air and burned gases inthe low-pressure cylinder 9 for the balance of the stroke (being cut offfrom the pressure in the high-pressure cylinder) are utilized by naturalexpansioinand are thus used more economically and the terminal pressurereduced to almost the pressure of the atmosphere. It will be observedthat owing to thc location of the cylinder-ports 21 and 22 withreference to the gas-ports l0 and 11 that the earlier the gas-supply iscut off (and conscquently the smaller is the explosive charge) theearlier is the connection cut off between the ports 21 and 22, and as aconsequence the higher is the compression in the higlrprcssure cylinder29 and explosion-chamber 3, and vice versa--that is, the larger inamount is the gascharge admitted to the pump, and consequently thelarger is the explosive charge-the lower is the compression of thecharge before ignition in the explosion chamber. This is a valuablefeature in my present engine, for by it the initial pressureafterignition of each explosion is anticipated, and the amount ofcompression best adapted for that explosion regulated in every instancebythe same slidevalve which regulates the amount of the gascharge, bothunder control ofthe same governor; and then,again,when thegas-chargeunder cumulatively high speed is cut oil" entirely by the pawl 43dropping out of range of the cam 42, Fig. 5, the compression of theair-charge is kept up to the maximum, ready for a renewal of the gascharge, so that when renewed again (by the springs 40 forcing the cam 42under the pawl 43) the best results of the explosion are attained. Ifthis were not so constructed, then,if an explosion were missed,the next011e following would not have the benefit of any compression at all, andwould, consequently,be very weak, and several would have to take placebefore one of a fairly high initial pressure were obtained. The resultwould be less economy in gas, and not so quick a regulation of speed;but with my cut-ofi', as herein lfO IIO

described, the compression varying with the gas charge inversely and theexplosive charge being always delivered to the igniter end of theexplosion-chamber, the governor can but be very sensitive, and theengine will respond quickly to its slightest changes of load.

The slide-valve is the Vprincipal cause of friction in mostgas-engines.- It is usually held to its face by stiff springs, whichhave to exert a pressure sufficient to overcome the highest initialpressure, which in some engines is two hundred and fifty pounds to thesquare inch. When the exhaust-valve opens, and there is no pressure atall in the cylinder, these springs are doing their full work just thesame, holding the slide up to its face with a force of over two hundredand fifty pounds, all of which has to be overcome by the engine, as theslide must be kept moving.

I balance my slide 5, Fig. 11, by having a place on its back 48 recessedout about one thirty-second of an inch deep and of equal area to thevport 20. A small hole, 49, connects the port 2() with the recess. ThenI have alight independent back slide, 450, (see Fig. 11,) which isfirmly held to a disk-diaphragm, 5l, by the screws 52. This diaphragm isof thin sheet-steel, aud acts as a spring to hold the independent backslide, 50, at all times with the pressure of a few pounds only againstthe main slide-valve 5. Between this diaphragm-spring 51 and theindependent back slide, 50, there is a thin airspace, equal in area tothe port 20. This diaphragm is iheld iirmly by the screw 53 to the xedguide 54, which guide is fastened to the outside of the cylinder orframe by the bolts 55. It will be observed that no matter what thepressure may be against the slide in the port 20 'it is reacted againstthe fixed guide 54, and that the only pressure on the slide at any timeis the amount due to the spring of the diaphragm 51,whichcau be adjustedto just sufficient in amount to prevent any leakage. The diaphragm underthe edges (at the screws 52) can be packed with ordinary sheet-rubberpacking.

The amount of extra clearance due to balancing the slide-valve in thismanner is almost nothing. Another form of this diaphragm-balance isshown in Fig. 2. I prefer, however, the one shown in Fig. 11. The otherend of the slide 5, which covers the gas-ports 10 and 11, (see Fig. 2 or11,) is held to its face by a very light spring, 75, as there is nopressure in the gas-ports to amount to anything.

The piston of my gas-measuring pump I drive from a crank fixed to theface of the governor case or guard 56, Fig. 3. The connecting-rod whichconnects to this crank-pin 56 is shown at 57 in Fig. 1.` Thisgas-measuring pump and its manner of operation are fully described in myapplication for patent on February 3, Serial No. 190,692.

In Fig. 1 is shown a boiler-iron air-tank, 58, located under the engineinside the frame, and

which is connected to the side of the cylinder by the pipe 59 and thevalves 60. detail in Fig.- 12.) The pipe 59 continues above the valves60 and opens into the portY 2l (see Fig. 2) at the point G1.

In Fig. 12 the valve 62 is the storage-valve. 63 is a check-valve, witha hand-screw, 64, by which it can be kept open against the spring 65.Vhen the engine is running, the valve 62 may be opened, and valve 63 isleft as a check-valve to be operated by the spring. The air and burnedgases under high pressure are forced throughthe check-valve 63 until thepressure in the air-tank 58 equals the pressure of the explosion. Thenvalve 62 may be tightly closed, and the contents of the airtank areready for use whenever the engine is to be started at some future time.In. starting, all that is required is to open valve 62 and alsocheck-valve 63 by screwing in the thumbscrew 64 and forcing the valveoff its seat. The compressed air enters the port 21 (see Fig. 2) at 6l;and no matter what position the crank may be in (if slightly oft'thecenter) the engine will startat once, the pressure of the air acting onboth pistons 1 and 23, the engine being for the time the same exactly asau ordinary double-acting steam-engine.

For ignition I use a small dynamo of about one-tenth horse power, anddrive the same with a small round belt from the governor case or guard.(See Fig. 3.)

I am aware that the use of a small dynamo to generate the ignitionelectric spark isnot new; but my devices connected with the poles of thewires forming the igniter are new, and are made so as to avoid thetrouble hitherto experienced of the gathering of soot on the insulatedpoles. The current is carried to the insulated rod 66, Fig. 2, which israised by the lever 7. The other end of the wire connects withinsulated-disk 67, which has the points or projections 68. The ends ofthe igniter 4 are in form of two springs,which are forced in between thepoints 68, which points are rough or corrugated on the inside edges, sothe rubbing of the sides of the spring ends 4 on the same will alwayspreserve both ends and points clean and free from carbon or soot. As thepistou reaches the limit of -its.outstroke, (from the crank,) the rod 66is raised through the metallic insulated stuffing-box 69, and theelectric current is broken, and an intense electric spark is generatedbetween the spring ends 4 and the projections 68. The exhaustvalve 70,Fig. 2, I drive with a small eccentric, ,71, Fig. 3, connecting totherod 41, Fig.

2. The stem of the valve has a relief-spring,` 72,which the eccentricworks against on half its stroke, and lifts and closes the valveduringthe other half, correspondingin time to one full instroke (towardthe crank) of the main pistou. The exhaust products are carried ofi' bythe pipe 7 3 into the cast-iron exhaust-pot 74 inside the frame, fromwhich they are carried off in the usual manner.

Having thus fully described my invention,

(Shown in IOO IIO

what I'claim as new, and desire to secure by Letters Patent, is-

1. In agus-engine, in combination with a gas-supply pump, a slide-valveoperated from a movable eccentric, which is controlled by a governor soas to cut off the gas-supply to said pump at varying points in thestroke, substantially as described.

2. In a gas-engine, in combination with a gas-supply pump,` aslide-valve regulating the supply to said pump and operated by aneccentric on the main shaft, the centers of said eccentric and saidshaft relatively to each other being dependent upon the position of theweights of a centrifugal governor relatively to their axial center,substantially for the purpose and as herein described.

3. In` a gas-engine, in combination with a gas-supply pump, aslide-valve regulating the supply to said pump and operated by arcvolving eccentric, which eccentric is movable radially and spirally onits shaft in a plane at right angles to the axis of said shaft, itsposition in that respect relatively to the center of the shaft dependingupon the speed of a centrifngal governor, substantially as and for thepurpose herein described.

4. In a compound gas-engine having on one valve-seat ports forconnecting the high and low pressure cylinders and for the supply of gasto a gas-supply pump, the combination, with the high and low pressurecylinders and the gas-supply pump, of a slide-valve act uating theabove-named ports and operated by an eccentric on a revolving shaft, thepositions of centers of said eccentric and said shaft relatively to eachotherbeing dependent upon the speed of a centrifugal governor, so as toshut off the connection between the two cylinders and the gas-supply atvarying points of the stroke according to the fluctuations of the speedof the engine, substantially as set forth.

5. In a compound gas-engine, in combination with ports to the high andlow pressure cylinders and to a gas-supply pump, all opening on the sameseat, a slide-valve actuating all said ports, substantially asdescribed.

6. In a gas-engine, a sleeve or thimble having a cam for opening agas-supply valve arranged to be moved by an eccentric on a revolvingshaft (the movement of said eccentric on said shaft being in a plane ata right angle to the axis of the shaft) out of contact with thegas-valve pawl or lever when the engine runs beyond a predeterminedspeed, thereby closing said valve until the speed lowers, substantiallyas and for the purpose herein described.

7. In a gas-engine, a sleeve or thimble having a cam for opening agas-valve, arranged to be moved by an eccentric on a revolving shaft, sotheu cam will be entirely to one side of the pawl or lever against aspring when the engine runs too fast, said spring` so fixed as to movethe cam in contact with the pawl again when the speed is reduced,substantially as and for the purpose herein described.

8. In a gas-engine having a movable sleeve or thimble with cam thereonfor opening the gas-inlet valve, lugs or projections on said sleeve forforcing said cam out of cont-act with the gas-valve pawl or lever whenthe engine runs too fast, substantially as and for the purpose hereindescribed.

f). In a gas-engine having a sliding sleeve or thimble with cam thereonfor opening the gas-inlet valve, lugs or projections on a movableeccentric for forcing said cam out of contact with the gas-valve pawl orlever when the engine runs too fast, substantially as and for thepurpose herein described.

l0. In a gas-engine, a valve and an automatic cut-olf governor arrangedso as to eut off' the gas-supply and cut oftl the outlet of theexplosion-cylinder, both at varying points in the stroke, so that thesmaller the gas charge admitted the greater is the compression of theexplosive charge before ignition, substantially as and for the purposeherein described.

21.1. In a compound gas-engine, the automatic eut-off governor with thelnovable eccentric, the length of the stroke of which is dependent uponthe speed of said governor, in combination with a slide-valve operatedby said eccentric, which controls admission of the gas charge and theconnection between the two cylinders, and the air-compressor in one endof the low-pressure cylinder, all substantial] y as and for the purposesherein described.

12. In a gas-engine, the centrifugal governor with the guard or shield,in combina tion with the crank-pin and the gas-measuring pump,substantially as and for the purpose herein described.

i3. In a gas-engine, an eleetricigniter consisting ot' thespring-forkedend, and the lugs provided with grooved edges, arranged sothat the spring end rubs the said edges when in contact and preservesthe points of contact free from soot and carbon, substantially as andfor the purpose herein described.

14. In a gas-engine, in combination witha small dynamo, the rod andlever 7, and the spring-pointed igniter, with the lugs to come incontact therewith, substantially as and for the purpose hereindescribed.

l5. In a gas-engine, a centrifugal governor and movable eccentric undercontrol of same, in combination with the sliding sleeve and cam, and thegas-inlet valve and a lever operating said valve by said ean1,substantially as and for the purpose herein described.

16. In a gas-engine, the movable eccentric on a revolving shaft,controlled in the length of its stroke by a centrifugal governor, incombination with the sliding sleeve, the double-ported slide-valve, andthe air-compressor and gas-measuring pump, substantially as and forthepurpose herein described.

JAS. FRANK PLA CE.

lfitiiesses:

.'I`. S. SnERnunNn, W. F. Six-init.

IOO

IIO

ISO

